User equipment involved in power saving

ABSTRACT

The present disclosure relates to a user equipment (UE), which comprises a receiver, which in operation, receives power saving signals, PoSS, from a serving base station on which the UE is camping, processing circuitry, which, in operation, monitors the reception of PoSS to determine a UE behavior regarding processing of a physical downlink control channel, PDCCH, wherein the PoSS comprises a behavior indication indicating for the UE to follow a first behavior or a second behavior, and wherein the PoSS further comprises a configuration indication indicating at least one configuration parameter associated with the first or second behavior, and wherein the processing circuitry, in operation, determines to perform PDCCH monitoring in case the first behavior is indicated and to skip PDCCH monitoring in case the second behavior is indicated, and accordingly applies the at least one configuration parameter.

BACKGROUND Technical Field

The present disclosure is directed to methods, devices, and articles incommunication systems, such as 3GPP communication systems.

Description of the Related Art

Currently, the 3rd Generation Partnership Project (3GPP) works at thetechnical specifications for the next generation cellular technology,which is also called fifth generation (5G).

One objective is to provide a single technical framework addressing allusage scenarios, requirements and deployment scenarios (see e.g.,section 6 of TR 38.913 version 15.0.0 incorporated herein by reference),at least including enhanced mobile broadband (eMBB), ultra-reliablelow-latency communications (URLLC), massive machine type communication(mMTC). For example, eMBB deployment scenarios may include indoorhotspot, dense urban, rural, urban macro and high speed; URLLCdeployment scenarios may include industrial control systems, mobilehealth care (remote monitoring, diagnosis and treatment), real timecontrol of vehicles, wide area monitoring and control systems for smartgrids; mMTC deployment scenarios may include scenarios with large numberof devices with non-time critical data transfers such as smart wearablesand sensor networks. The services eMBB and URLLC are similar in thatthey both demand a very broad bandwidth, however are different in thatthe URLLC service may preferably require ultra-low latencies.

A second objective is to achieve forward compatibility. Backwardcompatibility to Long Term Evolution (LTE, LTE-A) cellular systems isnot required, which facilitates a completely new system design and/orthe introduction of novel features.

Non-limiting and exemplary embodiments facilitate providing improvedprocedures for saving power in a user equipment.

In one general example, the techniques disclosed here feature a userequipment comprising a receiver, which in operation, receives powersaving signals, PoSS, from a serving base station on which the UE iscamping, and processing circuitry, which, in operation, monitors thereception of PoSS to determine a UE behavior regarding processing of aphysical downlink control channel, PDCCH. The PoSS comprises a behaviorindication indicating for the UE to follow a first behavior or a secondbehavior, and wherein the PoSS further comprises a configurationindication indicating at least one configuration parameter associatedwith the first or second behavior, wherein the processing circuitry, inoperation, determines to perform PDCCH monitoring in case the firstbehavior is indicated and to skip PDCCH monitoring in case the secondbehavior is indicated, and accordingly applies the at least oneconfiguration parameter.

In one general example, the techniques disclosed here feature a methodcomprising the following steps performed by the UE: Receiving powersaving signals, PoSS, from a serving base station on which the UE iscamping; monitoring the reception of PoSS to determine a UE behaviorregarding processing of a physical downlink control channel, PDCCH;wherein the PoSS comprises a behavior indication indicating for the UEto follow a first behavior or a second behavior, and wherein the PoSSfurther comprises a configuration indication indicating at least oneconfiguration parameter associated with the first or second behavior,and wherein the processing circuitry, determines to perform PDCCHmonitoring in case the first behavior is indicated and to skip PDCCHmonitoring in case the second behavior is indicated, and accordinglyapplies the at least one configuration parameter.

In one general example, the techniques disclosed here feature a basestation, BS, comprising a transmitter, which in operation, transmitspower saving signals, PoSS, to at least one user equipment, UE, which iscamping on the base station, and processing circuitry, which, inoperation, generates the PoSS. The PoSS comprises a behavior indicationindicating for the UE to follow a first behavior or a second behavior,and wherein the PoSS further comprises a configuration indicationindicating at least one configuration parameter associated with thefirst or second behavior, wherein the PoSS is generated to cause the UEto perform PDCCH monitoring in case the first behavior is indicated andto skip PDCCH monitoring in case the second behavior is indicated, andto accordingly apply the at least one configuration parameter.

It should be noted that general or specific embodiments may beimplemented as a system, a method, an integrated circuit, a computerprogram, a storage medium, or any selective combination thereof.

Additional benefits and advantages of the disclosed embodiments anddifferent implementations will be apparent from the specification andfigures. The benefits and/or advantages may be individually obtained bythe various embodiments and features of the specification and drawings,which need not all be provided in order to obtain one or more of suchbenefits and/or advantages.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In the following exemplary embodiments are described in more detail withreference to the attached figures and drawings.

FIG. 1 shows an exemplary architecture for a 3GPP NR system;

FIG. 2 shows an exemplary user and control plane architecture for theLTE eNB, gNB, and UE;

FIGS. 3A and 3B illustrate the messages exchanged between a gNB and a UEwhen performing a power saving procedure using PoSS;

FIG. 4 illustrates the exemplary and simplified structure of a UE and agNB;

FIG. 5 illustrates a structure of the UE according to an exemplaryimplementation of a first embodiment;

FIG. 6 is a flow diagram for the behavior of a UE, according to anexemplary implementation;

FIG. 7 is a flow diagram for the behavior of a UE, according to anotherexemplary implementation;

FIG. 8 is a timing diagram for the behavior of a UE, according to anexemplary implementation of a first behavior;

FIG. 9 is a timing diagram for the behavior of a UE, according to anexemplary implementation of a second behavior;

FIG. 10 illustrates a structure of a DCI according to an exemplaryimplementation of a first solution;

FIG. 11 illustrates a structure of a DCI according to another exemplaryimplementation of the first solution;

FIG. 12 illustrates a structure of a DCI according to an exemplaryimplementation of a second solution;

FIG. 13 illustrates a structure of a DCI according to another exemplaryimplementation of the second solution; FIG. 14 illustrates a structureof a DCI according to an exemplary implementation of a third solution;and

FIG. 15 illustrates a structure of a DCI according to another exemplaryimplementation of the third solution.

DETAILED DESCRIPTION 5G NR System Architecture and Protocol Stacks

3GPP is working at the next release for the 5^(th) generation cellulartechnology, simply called 5G, including the development of a new radioaccess technology (NR) operating in frequencies ranging up to 100 GHz.3GPP has to identify and develop the technology components needed forsuccessfully standardizing the NR system timely satisfying both theurgent market needs and the more long-term requirements. In order toachieve this, evolutions of the radio interface as well as radio networkarchitecture are considered in the study item “New Radio AccessTechnology”. Results and agreements are collected in the TechnicalReport TR 38.804 v14.0.0, incorporated herein in its entirety byreference.

Among other things, the overall system architecture assumes an NG-RAN(Next Generation—Radio Access Network) that comprises gNBs, providingthe NG-radio access user plane (SDAP/PDCP/RLC/MAC/PHY) and control plane(RRC) protocol terminations towards the UE. The gNBs are interconnectedwith each other by means of the Xn interface. The gNBs are alsoconnected by means of the Next Generation (NG) interface to the NGC(Next Generation Core), more specifically to the AMF (Access andMobility Management Function) (e.g., a particular core entity performingthe AMF) by means of the NG-C interface and to the UPF (User PlaneFunction) (e.g., a particular core entity performing the UPF) by meansof the NG-U interface. The NG-RAN architecture is illustrated in FIG. 1(see e.g., 3GPP TS 38.300 v15.2.0, section 4 incorporated herein byreference).

Various different deployment scenarios can be supported (see e.g., 3GPPTR 38.801 v14.0.0 incorporated herein by reference). For instance, anon-centralized deployment scenario (see e.g., section 5.2 of TR 38.801;a centralized deployment is illustrated in section 5.4) is presentedtherein, where base stations supporting the 5G NR can be deployed. FIG.2 illustrates an exemplary non-centralized deployment scenario (seee.g., FIG. 5.2.-1 of said TR 38.801), while additionally illustrating anLTE eNB as well as a user equipment (UE) that is connected to both a gNBand an LTE eNB. The new eNB for NR 5G may be exemplarily called gNB. AneLTE eNB is the evolution of an eNB that supports connectivity to theEPC (Evolved Packet Core) and the NGC (Next Generation Core).

The user plane protocol stack for NR (see e.g., 3GPP TS 38.300 v15.2.0,section 4.4.1 incorporated herein by reference) comprises the PDCP(Packet Data Convergence

Protocol, see section 6.4 of TS 38.300), RLC (Radio Link Control, seesection 6.3 of TS 38.300) and MAC (Medium Access Control, see section6.2 of TS 38.300) sublayers, which are terminated in the gNB on thenetwork side. Additionally, a new access stratum (AS) sublayer (SDAP,Service Data Adaptation Protocol) is introduced above PDCP (see e.g.,sub-clause 6.5 of 3GPP TS 38.300 version 15.2.0 incorporated herein byreference). A control plane protocol stack is also defined for NR (seefor instance TS 38.300, section 4.4.2). An overview of the Layer 2functions is given in sub-clause 6 of TS 38.300. The functions of thePDCP, RLC, and MAC sublayers are listed respectively in sections 6.4,6.3, and 6.2 of TS 38.300. The functions of the RRC layer are listed insub-clause 7 of TS 38.300. The mentioned sections of TS 38.300 areincorporated herein by reference.

For instance, the Medium-Access-Control layer handles logical-channelmultiplexing, and scheduling and scheduling-related functions, includinghandling of different numerologies.

For the physical layer, the MAC layer uses services in the form oftransport channels. A transport channel can be defined by how and withwhat characteristics the information is transmitted over the radiointerface. The Random-Access Channel (RACH) is also defined as atransport channel handled by MAC, although it does not carry transportblocks. One of procedures supported by the MAC layer is the RandomAccess Procedure.

The physical layer (PHY) is, for example, responsible for coding, PHYHARQ processing, modulation, multi-antenna processing, and mapping ofthe signal to the appropriate physical time-frequency resources. It alsohandles mapping of transport channels to physical channels. The physicallayer provides services to the MAC layer in the form of transportchannels. A physical channel corresponds to the set of time-frequencyresources used for transmission of a particular transport channel, andeach transport channel is mapped to a corresponding physical channel.One physical channel is the PRACH (Physical Random Access Channel) usedfor the random access.

Use cases/deployment scenarios for NR could include enhanced mobilebroadband (eMBB), ultra-reliable low-latency communications (URLLC),massive machine type communication (mMTC), which have diverserequirements in terms of data rates, latency, and coverage. For example,eMBB is expected to support peak data rates (20 Gbps for downlink and 10Gbps for uplink) and user-experienced data rates in the order of threetimes what is offered by IMT-Advanced. On the other hand, in case ofURLLC, the tighter requirements are put on ultra-low latency (0.5 ms forUL and DL each for user plane latency) and high reliability (1-10⁻⁵within lms). Finally, mMTC may preferably require high connectiondensity (1,000,000 devices/km² in an urban environment), large coveragein harsh environments, and extremely long-life battery for low costdevices (15 years).

Therefore, the OFDM numerology (e.g., subcarrier spacing, OFDM symbolduration, cyclic prefix (CP) duration, number of symbols per schedulinginterval) that is suitable for one use case might not work well foranother. For example, low-latency services may preferably require ashorter symbol duration (and thus larger subcarrier spacing) and/orfewer symbols per scheduling interval (aka, TTI) than an mMTC service.Furthermore, deployment scenarios with large channel delay spreads maypreferably require a longer CP duration than scenarios with short delayspreads. The subcarrier spacing should be optimized accordingly toretain the similar CP overhead. NR may support more than one value ofsubcarrier spacing. Correspondingly, subcarrier spacing of 15kHz, 30kHz,60 kHz . . . are being considered at the moment. The symbol durationT_(u) and the subcarrier spacing Δf are directly related through theformula Δf=1/T. In a similar manner as in LTE systems, the term“resource element” can be used to denote a minimum resource unit beingcomposed of one subcarrier for the length of one OFDM/SC-FDMA symbol.

In the new radio system 5G-NR for each numerology and carrier a resourcegrid of subcarriers and OFDM symbols is defined respectively for uplinkand downlink. Each element in the resource grid is called a resourceelement and is identified based on the frequency index in the frequencydomain and the symbol position in the time domain. (See 3GPP TS 38.211v15.2.0 incorporated herein by reference).

Control Signaling/ PDCCH/ DCI/Search Spaces

The main purpose of DCI (Downlink Control Information) in 5G NR is thesame as DCI in LTE, namely being a special set of information thatschedules a downlink data channel (e.g., the PDSCH) or an uplink datachannel (e.g., PUSCH). In 5G NR there are a number of different DCIFormats defined (see e.g., TS 38.212 v15.2.0 section 7.3.1 incorporatedherein by reference). An overview is given by the following table.

DCI format Usage 0_0 Scheduling of PUSCH in one cell 0_1 Scheduling ofPUSCH in one cell 1_0 Scheduling of PDSCH in one cell 1_1 Scheduling ofPDSCH in one cell 2_0 Notifying a group of UEs of the slot format 2_1Notifying a group of UEs of the PRB(s) and OFDM symbol(s) where UE mayassume no transmission is intended for the UE 2_2 Transmission of TPCcommands for PUCCH and PUSCH 2_3 Transmission of a group of TPC commandsfor SRS transmissions by one or more UEs

PDCCH search spaces are areas in the downlink resource grid(time-frequency resources) where a PDCCH (DCI) may be carried. Putbroadly, a radio resource region is used by a base station to transmitcontrol information in the downlink to one or more UEs. The UE performsblind decoding throughout search space trying to find PDCCH data (DCI).Conceptually, the Search Space concept in 5G NR is similar to LTE SearchSpace, but there are many differences in terms of the details.

Synchronization Signal Block Measurement TimingConfiguration—SMTC—PSS/SSS, PBCH

NR has introduced the so-called synchronization signal block, SS block(SSB), which comprises a Primary Synchronization Signal (PSS), aSecondary Synchronization Signal (SSS), and a Physical Broadcast CHannel(PBCH). The PSS and SSS can be used by UEs to find, synchronize to andidentify a network. The PBCH carries a minimum amount of systeminformation including an indication where the remaining broadcast systeminformation is transmitted.

In LTE, these three signals were also used, the PSS, SSS, and PBCH,although not as being part of one SSB. The three SSB components arealways transmitted together in NR, e.g., they have the same periodicity.A given SSB may be repeated within an SS burst set, which can bepotentially used for a gNB beam-sweeping transmission. The SS burst setmay be confined to a particular time period, such as a 5 ms window. Forinitial cell selection, the UE may assume a default SS burst setperiodicity of 20 ms.

The 5G NR PSS is Physical Layer specific signal to identify the radioframe boundary and is type of an m-sequence. The 5G NR SSS is also aPhysical-Layer specific signal to identify the subframe boundary and isalso an m-sequence. (See e.g., TS 38.211 v15.2.0 section 7.4.2incorporated herein by reference).

Reference Signals

As in LTE, several different types of reference signals (RS) are usedfor 5G NR (see 3GPP TS 38.211 v15.3.0 section 7.4.1 incorporated hereinby reference). At least the following reference signals are available in5G NR:

-   -   CSI-RS, Channel State Information Reference Signal, usable for        channel state information acquisition and beam management.    -   PDSCH DMRS, DeModulation Reference Signal, usable for the PDSCH        demodulation.    -   PDCCH DMRS, DeModulation Reference Signal, usable for the PDCCH        demodulation.    -   PBCH DMRS, DeModulation Reference Signal, usable for the PBCH        demodulation.    -   PTRS, Phase Tracking Reference Signal, usable for phase tracking        the PDSCH.    -   Tracking Reference Signal, usable for time tracking.

Further, PBCH DMRS can be exemplarily seen as part of the SSB-referencesignals (see 3GPP TS 38.215 v15.3.0 section 5.1.1 “SS reference signalreceived power (SS-RSRP)”).

The main differences between reference signals in 5G NR communicationsystems and reference signals in LTE are that in 5G NR, there is noCell-specific reference signal, that a new reference signal PTRS hasbeen introduced for time/phase tracking, that DMRS has been introducedfor both downlink and uplink channels, and that in NR, the referencesignals are transmitted only when it is necessary.

As a DL-only signal, the CSI-RS, which the UE receives, is used toestimate the channel and report channel quality information back to thegNB. During MIMO operations, NR may use different antenna approachesbased on the carrier frequency. At lower frequencies, the system uses amodest number of active antennas for MU-MIMO and adds FDD operations. Inthis case, the UE may use the CSI-RS to calculate the CSI and report itback in the UL direction. The CSI-RS can be further characterizedaccording to the following:

-   -   It is used for DL CSI acquisition.    -   Used for RSRP measurements during mobility and beam management.    -   Also used for frequency/time tracking, demodulation and UL        reciprocity based pre-coding.    -   CSI-RS is configured specific to UE, but multiple users can also        share the same resource.    -   5G NR standard allows high level of flexibility in CSI-RS        configurations, a resource can be configured with up to 32        ports.    -   CSI-RS resource may start at any OFDM symbol of the slot and it        usually occupies 1/2/4 OFDM symbols depending upon configured        number of ports.    -   CSI-RS can be periodic, semi-persistent or aperiodic (due to DCI        triggering).    -   For time/frequency tracking, CSI-RS can either be periodic or        aperiodic. It is transmitted in bursts of two or four symbols        which are spread across one or two slots.

Quasi-Co-Location (QCL) Concept

The quasi-co-location (QCL) concept is exploited in LTE and NR and maybe explained in a simplified manner as follows: If two signals are QCL,it means the UE can assume the same reception/transmission parameter inlarge scale channel parameters, e.g., Doppler shift, Doppler spread,average delay, delay spread, spatial received parameter and beamorientations. This helps to improve the channel estimation and receptionperformance.

As mentioned above, conventionally, the UE is performing PDCCHmonitoring and blind decoding, which is not always needed, thusunnecessarily wasting energy.

Consequently, the inventors have identified the possibility to reducethe expenditure for PDCCH monitoring and blind decoding by providing aPower Saving Signal, PoSS, which allows for either triggering the UE tomonitor PDCCH or to indicate to the UE to skip PDCCH monitoring until apredetermined time point. When the UE skips the PDCCH monitoring, the UEactive time can be shortened, which saves power. As illustrated in FIG.3, the base station sends a PoSS to the UE which generally may cause theUE to follow two different behaviors. In a first behavior, which isshown in FIG. 3A, the PoSS indicates to the UE that it should monitorthe PDCCH. In this case, the UE receives the PDCCH and sends back ascheduled transmission in accordance with the received PDCCH. On theother hand, if the PoSS indicates to the UE to follow a second behavior,the UE skips monitoring the PDCCH as schematically illustrated in FIG.3B. Thus, the gNB will not transmit any PDCCH to the UE. Even if a PDCCHwould be transmitted, the UE would not be able to receive it.

In the following, UEs, base stations, and procedures to meet these needswill be described for the new radio access technology envisioned for the5G mobile communication systems, but which may also be used in LTEmobile communication system. Different implementations and variants willbe explained as well. The following disclosure was facilitated by thediscussions and findings as described above and may, for example, bebased at least on part thereof.

In general, it should be noted that many assumptions have been madeherein so as to be able to explain the principles underlying the presentdisclosure in a clear and understandable manner. These assumptions arehowever to be understood as merely examples made herein for illustrationpurposes that should not limit the scope of the disclosure. A skilledperson will be aware that the principles of the following disclosure andas laid out in the claims can be applied to different scenarios and inways that are not explicitly described herein.

Moreover, some of the terms of the procedures, entities, layers, etc.,used in the following are closely related to LTE/LTE-A systems or toterminology used in the current 3GPP 5G standardization, even thoughspecific terminology to be used in the context of the new radio accesstechnology for the next 3GPP 5G communication systems is not fullydecided yet. Thus, terms could be changed in the future, withoutaffecting the functioning of the embodiments. Consequently, a skilledperson is aware that the embodiments and their scope of protectionshould not be restricted to particular terms exemplarily used herein forlack of newer or finally agreed terminology but should be more broadlyunderstood in terms of functions and concepts that underlie thefunctioning and principles of the present disclosure.

For instance, a mobile station or mobile node or user terminal or userequipment (UE) is a physical entity (physical node) within acommunication network. One node may have several functional entities. Afunctional entity refers to a software or hardware module thatimplements and/or offers a predetermined set of functions to otherfunctional entities of the same or another node or the network. Nodesmay have one or more interfaces that attach the node to a communicationfacility or medium over which nodes can communicate. Similarly, anetwork entity may have a logical interface attaching the functionalentity to a communication facility or medium over which it maycommunicate with other functional entities or correspondent nodes.

The term “base station” or “radio base station” here refers to aphysical entity within a communication network. As with the mobilestation, the base station may have several functional entities. Afunctional entity refers to a software or hardware module thatimplements and/or offers a predetermined set of functions to otherfunctional entities of the same or another node or the network. Thephysical entity performs some control tasks with respect to thecommunication device, including one or more of scheduling andconfiguration. It is noted that the base station functionality and thecommunication device functionality may be also integrated within asingle device. For instance, a mobile terminal may implement alsofunctionality of a base station for other terminals. The terminologyused in LTE is eNB (or eNodeB), while the currently used terminology for5G NR is gNB.

FIG. 4 illustrates a general, simplified and exemplary block diagram ofa user equipment (also termed communication device) and a schedulingdevice (here exemplarily assumed to be located in the base station,e.g., the eLTE eNB (alternatively termed ng-eNB) or the gNB in 5G NR).The UE and eNB/gNB are communicating with each other over a (wireless)physical channel respectively using the transceiver.

The communication device may comprise a transceiver and processingcircuitry. The transceiver in turn may comprise and/or function as areceiver and a transmitter. The processing circuitry may be one or morepieces of hardware such as one or more processors or any LSIs. Betweenthe transceiver and the processing circuitry there is an input/outputpoint (or node) over which the processing circuitry, when in operation,can control the transceiver, i.e., control the receiver and/or thetransmitter and exchange reception/transmission data. The transceiver,as the transmitter and receiver, may include the RF (radio frequency)front including one or more antennas, amplifiers, RFmodulators/demodulators and the like. The processing circuitry mayimplement control tasks such as controlling the transceiver to transmituser data and control data provided by the processing circuitry and/orreceive user data and control data, which is further processed by theprocessing circuitry. The processing circuitry may also be responsiblefor performing other processes such as determining, deciding,calculating, measuring, etc. The transmitter may be responsible forperforming the process of transmitting and other processes relatedthereto. The receiver may be responsible for performing the process ofreceiving and other processes related thereto, such as monitoring achannel. The solutions offered in the following will be described mainlyin connection with the 5G NR standardization for the unlicensedoperation (e.g., standalone or dual connectivity). Nevertheless, asalready hinted at above, the present concepts, ideas and improvementsare not restricted to 5G NR Unlicensed standardization but are equallyapplicable to the licensed operation of 5G NR and also to the unlicensedand/or licensed operation in LTE-(A) communication systems. Also futurecommunication systems may benefit from the concepts disclosed herein.

A first embodiment will be described in the following with regard toFIGS. 5 and 6.

FIG. 5 illustrates a simplified and exemplary UE structure according tothe present solution and can be implemented based on the general UEstructure explained in connection with FIG. 4 above. The variousstructural elements of the UE illustrated in said figure can beinterconnected between one another e.g., with corresponding input/outputnodes (not shown) e.g., in order to exchange control and user data andother signals. Although not shown for illustration purposes, the UE mayinclude further structural elements.

As apparent therefrom, the UE may include a power saving signalreceiver, a power saving signal monitoring circuitry, a behaviordetermination circuitry, as well as a configuration selection circuitryin order to participate in the improved procedures for reducing the UEpower expenditure as will be explained in the following.

In the present case as will become apparent from the below disclosure,the processor (processing circuitry) can thus be exemplarily configuredto at least partly perform one or more of the following steps ofmonitoring for the reception of power saving signals, PoSS, from aserving base station on which the UE is camping, to determine a UEbehavior regarding processing of a physical downlink control channel,PDCCH, wherein the PoSS comprises a behavior indication indicating forthe UE to follow a first behavior or a second behavior, and wherein thePoSS further comprises a configuration indication indicating at leastone configuration parameter associated with the first or secondbehavior. The processor determines to perform PDCCH monitoring in casethe first behavior is indicated and to skip PDCCH monitoring in case thesecond behavior is indicated, and accordingly applies the at least oneconfiguration parameter.

The receiver can in turn be configured to be able to at least partlyperform one or more of the following steps of receiving the power savingsignals, and of receiving information on the threshold values via systeminformation or configuration messages (such as of the RRC protocol).

FIG. 6 is a sequence diagram for the UE behavior according to thisimproved power saving procedure.

It is exemplarily assumed that the UE is in an idle mode, but it is alsopossible that the UE is in a connected mode. The radio cell the UE iscurrently camping on is exemplarily termed in the following servingradio cell, controlled by a serving base station.

As shown in FIG. 6, the UE first receives the PoSS and ascertains thatit has received the PoSS correctly. Next, the UE determines the behaviorindication of the PoSS. Two possible behaviors may be indicated: A firstbehavior may include to perform PDCCH monitoring, whereas a secondbehavior may include skipping the PDCCH monitoring and thus savingenergy. Depending on which behavior is indicated, the UE next evaluatesthe configuration indication of the PoSS and accordingly either performsthe PDCCH monitoring and applies the configuration parameter(s)associated with the first behavior. Otherwise, the UE evaluates theconfiguration indication of the DCI and skips the PDCCH monitoring. Inthis case, the UE applies the configuration parameter(s) associated withthe second behavior.

The process may return to the step of checking whether a PoSS isdetected.

FIG. 7 shows a sequence diagram for the UE behavior according to anotherexemplary improved power saving procedure. In a first step, it has to beascertained that the UE is configured by the base station to monitorpower saving signals, PoSS. If not, the process goes back to the startupprocedure. On the other hand, if the UE is configured to monitor thePoSS, in the next step the UE receives and monitors for receiving thePoSS, which according to an exemplary implementation may be in the formof a DCI. In case no PoSS is detected, the UE performs a defaultbehavior. In an exemplary implementation, the default behavior isdefined as the behavior in case the PoSS is misdirected by the UE. Then,the UE has no behavior indication from the PoSS DCI. In particular, itis shown in the flow diagram that in case no PoSS is detected, the UEmay have two different possibilities of a default behavior. If the UE isin a state of Discontinuous Reception, DRX, where it is ON (“DRX ON”),the UE may just perform regular PDCCH monitoring. Alternatively, thedefault behavior in case no PoSS is detected may also be not to monitorPDCCH during DRX_OFF.

In case that a PoSS is detected, the UE evaluates a behavior indicationcomprised in the DCI of the PoSS. From this behavior indication, the UEdetermines whether the indicated UE behavior is to skip PDCCH monitoringor to perform PDCCH monitoring. If the behavior indication indicatesthat PDCCH monitoring is to be performed, a configuration indication ofthe DCI is evaluated and configuration parameters which are associatedwith a first behavior are applied. According to the present embodiment,the first behavior involves monitoring of the PDCCH and thus does notprovide any energy saving features.

On the other hand, if the behavior indication indicates that PDCCHmonitoring is to be skipped, the evaluation of the configurationindication induces the UE to apply at least one configuration parameterassociated with a second behavior. The second behavior is associatedwith energy saving and in particular comprises skipping the PDCCHmonitoring.

The process may return to the step of checking whether a PoSS isdetected.

FIG. 8 illustrates the first behavior of the UE in a timing diagramaccording to an exemplary aspect. According to this embodiment, the UEmonitors a power saving signal, PoSS, which may also be referred to as apower saving channel, in the configured resource.

As will be explained later in more detail, the first behavior comprisesgenerally triggering the UE to start monitoring PDCCH. If no triggeringis detected, the UE default behavior may for instance be not to receiveand decode PDCCH. This means that the base station may need to schedulethe UE shortly. To facilitate saving power, the interval between thisindication and a real scheduling can be as short as possible. To thisend, the UE needs to start performing time/frequency tracking, automaticgain control, AGC, training, Channel State Information, CSI/RadioResource Management, RRM, measurement and reporting, and SoundingReference Signal, SRS, transmission. In this way, the base stationacquires the downlink/uplink, DL/UL, channel conditions timely and isable to start scheduling shortly. Then, the total UE active time can beshortened which saves power. Furthermore, in order to save power, PDCCHmonitoring can be reduced by further indication of the Control ResourceSet, CORESET, the search space information, and/or a set of slots.

As schematically and exemplarily depicted in the diagram of FIG. 8, theUE ramps up before it receives a Synchronization Signal Block, SSB,burst and shortly thereafter the PoSS indicating to start PDCCHmonitoring. In a warming up block, the UE receives reference signals,RS, for time and/or frequency tracking, automatic gain control, AGC,Channel State Information, CSI, reference resources, and Radio ResourceManagement, RRM, reference resources. Furthermore, CSI reportingresources, and finally, Sounding Reference Signal, SRS, transmissionresources are available to the UE.

As depicted in FIG. 8, the UE remains active over the next two SSBbursts, and then returns into an inactive state.

FIG. 9 shows, in contrast to FIG. 8, a timing diagram for the case thatthe UE receives a PoSS indicating that the UE should skip PDCCHmonitoring. This may be called a second behavior of the UE in thepresent disclosure. In this situation, the UE ramps down after havingreceived the PoSS and remains inactive during the OFF duration.Exemplarily, the OFF duration lasts over more than two SSB bursts.

In particular, the PoSS may indicate to the UE to skip PDCCH monitoringuntil a defined time point. If no PoSS is detected, the default behaviorof the UE may be to receive the PDCCH.

For the second behavior, no further time/frequency tracking, AGCtraining, CSI/RRM measurement/reporting, or SRS transmission is needed.The UE can be instructed that it does not need to receive the PDCCHuntil a next semi-static DRX cycle, or until the next occasion ofreceiving a configured PoSS. Alternatively, the UE can be instructedthat it does not need to receive the PDCCH in the next X slot, wherein Xcan be dynamically indicated or semi-statically configured.

Furthermore, besides being instructed that it does not need to receivethe PDCCH, the UE may also be indicated that the UE does not need toreceive the PoSS until a next semi-static DRX cycle, or until the nextoccasion of receiving a configured PoSS. Alternatively, the UE can beinstructed that it does not need to receive the PoSS in the next X slot,wherein X can be dynamically indicated or semi-statically configured.

In order to provide a PoSS which is able to indicate the first andsecond behavior to the UE as required, it is proposed to transmit a PoSSDCI to the UE which allows to integrate the different functionalities ofPDCCH monitoring triggering and skipping into one DCI design.

Generally, one DCI is shared by UE behavior indication for both thePDCCH monitoring and triggering. Consequently, the UE only needs todecode one unified PoSS DCI for accessing the further behaviorindication. Exemplarily, three concepts can be used to this end, whichwill be explained below in more detail. Firstly, the detailed UEbehavior indication (i.e., configuration) is encoded into a secondfield, which may be based on the interpretation of a first field.Secondly, the indication for skipping and triggering PDCCH monitoring aswell as the configuration indication may be jointly encoded in only onecommon field. Thirdly, the indication interpretation for skipping ortriggering PDCCH monitoring is based on a detected Radio NetworkTemporary Identifier, RNTI, while the configuration for the indicatedbehavior is the encoded into another field of the PoSS.

Moreover, the PoSS DCI may be UE group specific or UE specific. For theUE group specific case, the manner the bitmap is structured may besimilar to the existing NR DCI format_ *. Each UE may be exemplarilyconfigured with an index to address its own indication within the DCI,and thus allows the UE to determine which indication within theUE-group-specific PoSS is for itself.

Solution 1—First and second field

A first exemplary solution of the PoSS DCI will now be explainedreferring to FIG. 10. According to this solution, the DCI comprises afirst field and a second field.

The first field comprises, for instance one bit, which indicates to theUE that either the behavior of performing PDCCH monitoring (firstbehavior), or the behavior of skipping PDCCH monitoring (secondbehavior) is required. In accordance with the indicated behavior, the UEprocesses a second field which indicates the configuration associatedwith the first or second behavior. The second field may be arrangeddirectly consecutive to the respective first field and contains anidentifier linked to a previously configured table.

According to one exemplary implementation, the first field indicatesregarding the PDCCH monitoring to perform the monitoring or not toperform the monitoring, where the default behavior of the UE is not tomonitor the PDC CH. Alternatively, the first field indicates either toskip or not to skip monitoring the PDCCH. In this case, the defaultbehavior is not to skip the PDCCH monitoring.

According to the embodiment shown in FIG. 10, a second field is providedin the DCI which is interpreted according to the indication of the firstfield. The second field comprises a configuration indication whichdepends on the content of the first field. For instance, if the firstfield indicates to perform monitoring PDCCH, the UE interprets thesecond field to indicate at least one configuration related to how tomonitor the PDCCH, such as one or a combination of:

-   -   Channel State Information (CSI) reference resources,    -   Radio resource management (RRM) reference resources,    -   CSI reporting resources,    -   RRM reporting resources,    -   Sounding Reference Signal, SRS, transmission resources,    -   quasi-co-location of CSI/RRM reference resources,    -   quasi-co-location of CSI report resources, RRM report resources        and/or SRS transmission resources,    -   Control-Resource Set, CORESET information,    -   Search space information,    -   a set of slots for PDCCH monitoring,    -   PoSS monitoring skipping within certain time or frequency        resources, meaning e.g., that once the UE is indicated by the        PoSS to start monitoring the PDCCH, the following PoSS        monitoring can be skipped or partially skipped,    -   Hybrid Automatic Repeat Request-Acknowledgement, HARQ-ACK,        resource parameter indication.

For instance, these configuration parameters may be comprised in a firsttable associated with the first behavior.

On the other hand, if the first field indicates not to monitoring PDCCH,the UE interprets the second field to configure how to skip monitoringthe PDCCH, such as, for example, indicating at least one or acombination of the following configurations: skipping PDCCH monitoringand/or PoSS monitoring until the next semi-static DRX cycle, or untilthe next occasion of a configured power saving signal/channel, or in thenext X slots, wherein X is dynamically indicated or semi-staticallyconfigured, in case the first field indicates skipping PDCCH monitoring.

These configuration parameters may be comprised in a second tableassociated with the second behavior.

For both types of indication, the behavior and/or configurationparameter combinations may be configured by radio resource control, RRC.

Moreover, as shown in FIG. 11, the present improvement may also beimplemented with a UE-group-specific PoSS DCI. Here, the DCI comprises abitmap pattern, which in each bitmap has a first field and a secondfield for each UE of one group of UE (e.g., UE#1, UE#2, and UE#3). InFIG. 11, three UEs are depicted exemplarily. However, it is clear for aperson skilled in the art, that also more than three UEs may of coursealso be addressed by this PoSS DCI. As mentioned above, the gNB and theUE might exchange an index value with regard to this group-specific PoSSDCI, so as to allow the UE to determine which one of the various sets ofirst and second field is intended for itself.

Solution 2—Combined field

A second exemplary solution of the PoSS DCI will now be explainedreferring to FIG. 12.

According to this solution, the PoSS DCI comprises a combined field forbehavior indication and configuration indication, either for the firstor the second behavior.

As shown in FIG. 12, the PoSS DCI comprises a common field that jointlyencodes the information of skipping, triggering, and the relatedconfiguration parameters according to the required UE behavior. Forinstance, the bitmap for a UE may comprise a 3-bit word representing anindication index of a configuration table. Table 1 below depicts anexample of such a combined configuration table.

TABLE 1 HARQ- ACK resource CSI CSI Quasi- related Indication referencereport SRS co- PDCCH parameter index resource resource resource locationmonitoring value 000 Resource#a Resource#1 Resource#2 TRUE TRUE x 001Resource#b Resource#3 Resource#4 TRUE TRUE y 010 Resource#c Resource#5Resource#6 FALSE TRUE z . . . 111 NA NA NA NA FALSE NA

The entries in Table 1 may be configured e.g., by RRC. As mentionedabove, the respective bitmap in the common field selects one line and,consequently, one set of configuration parameters and the behavior(column “PDCCH monitoring” being TRUE or FALSE).

As shown in Table 1, the number may be unbalanced between thoseconfiguration parameters applicable to performing the PDCCH monitoringand those configuration parameters relating to the case of skipping thePDCCH monitoring. Overall, the joint encoding in the common field shownin FIG. 12 allows for a reduced overhead compared, e.g., to the abovedescribed Solution 1.

The present improvement may also be implemented with a UE group-specificPoSS DCI. According to FIG. 13, the PoSS DCI comprises a bitmap patternwhich has a combined field for each UE of one group of UE (e.g., UE#1,UE#2, and UE#3). In FIG. 11, three UEs are depicted exemplarily.However, it is clear for a person skilled in the art, that only one UEor more than three UEs may of course also be addressed by this PoSS DCI.

As shown in FIG. 13, the PoSS DCI comprises a bitmap for each UE of onegroup that jointly encodes the information of skipping, triggering, andthe related configuration parameters according to the required UEbehavior. For instance, the bitmap for each UE may comprise a 3-bit wordrepresenting an indication index of a configuration table. Table 1depicts an example of such a combined configuration table.

Solution 3 —Using RNTI and PoSS DCI field

A third exemplary solution of the PoSS DCI will now be explainedreferring to FIG.

14. According to this solution, the DCI comprises a field comprising anindication indicating the configuration in case of the first behavior,or a field comprising an indication indicating the configuration in caseof the second behavior. Furthermore, according to the third embodiment,different RNTIs are used for indicating the intended behavior as well asfor addressing the particular UE.

For instance, different RNTIs are used for masking the Cyclic RedundancyCheck (CRC) value of the PoSS DCI depending on whether PDCCH monitoringis to be performed or skipped.

As shown in FIG. 14, within the DCI of the detected PoSS the CRC istransmitted together with a field containing the indication of at leastone particular configuration parameter associated with either the firstor the second behavior. The field may for instance comprise 3 bits.

For instance, if the CRC descrambling check reveals an RNTI correlatedwith skipping the PDCCH monitoring, the UE interprets the indicationfield in the PoSS DCI as an indication of configuration parametersrelated to skipping the PDCCH monitoring. For instance, the UE knows howlong it can remain in a sleep mode.

On the other hand, if the CRC descrambling check reveals an RNTIcorrelated with performing the PDCCH monitoring, the UE interprets theindication in the PoSS DCI as indicating a configuration associated withthe first behavior. For instance, the UE accesses a table as shown belowas Table 2 and retrieves a set of configuration parameters and thenknows where to transmit CSI report and SRS transmission and then startsPDCCH monitoring. It is also possible that an update is performed.

TABLE 2 HARQ- ACK resource CSI Quasi- related Indication reference CSIreport SRS co- parameter index resource resource resource location value000 Re source#a Resource#1 Resource#2 TRUE x 001 Resource#b Resource#3Resource#4 TRUE y 010 Resource#c Resource#5 Resource#6 FALSE z . . . 111NA NA NA NA NA

The configuration entries for the triggering or skipping indication mayfor instance be configured by RRC together with the particular first andsecond RNTIs relating to the first and second behavior, respectively.

The present improvement may also be implemented with a UE-group-specificPoSS DCI, as shown in FIG. 15. According to this embodiment, the DCIcomprises a bitmap pattern, which in each bitmap has a field for each UEof one group of UE (e.g., UE#1, UE#2, and UE#3). In FIG. 15, three UEsare depicted exemplarily. However, it is clear for a person skilled inthe art, that only one UE or more than three UEs may of course also beaddressed by this PoSS DCI. Furthermore, according to the thirdembodiment, different RNTIs are used for indicating the intendedbehavior as well as for addressing the particular UE.

The respective UE of each group accesses the proper field according tothe serial position of this field in the complete bitmap pattern basedon a previously defined index.

Further Aspects

According to a first aspect, a user equipment is provided, whichcomprises a receiver, which in operation, receives power saving signals,PoSS, from a serving base station on which the UE is camping, processingcircuitry, which, in operation, monitors the reception of PoSS todetermine a UE behavior regarding processing of a physical downlinkcontrol channel, PDCCH, wherein the PoSS comprises a behavior indicationindicating for the UE to follow a first behavior or a second behavior,and wherein the PoSS further comprises a configuration indicationindicating at least one configuration parameter associated with thefirst or second behavior, and wherein the processing circuitry, inoperation, determines to perform PDCCH monitoring in case the firstbehavior is indicated and to skip PDCCH monitoring in case the secondbehavior is indicated, and accordingly applies the at least oneconfiguration parameter.

According to a second aspect provided in addition to the first aspect,in case the first field indicates performing PDCCH monitoring, the atleast one configuration parameter comprises at least one or acombination of:

-   -   Channel State Information (CSI) reference resources,    -   Radio resource management (RRM) reference resources,    -   CSI reporting resources,    -   RRM reporting resources,    -   Sounding Reference Signal, SRS, transmission resources,    -   quasi-co-location of CSI/RRM reference resources,    -   quasi-co-location of CSI report resources, RRM report resources        and/or SRS transmission resources,    -   Control-Resource Set, CORESET information,    -   Search space information,    -   a set of slots for PDCCH monitoring,    -   PoSS monitoring skipping,    -   Hybrid Automatic Repeat Request-Acknowledgement, HARQ-ACK,        resource parameter indication.

According to a third aspect provided in addition to the first or secondaspect, the at least one configuration parameter comprises one ofskipping PDCCH monitoring and/or PoSS monitoring until the nextsemi-static DRX cycle, or until the next occasion of a configured powersaving signal/channel, or in the next X slots, wherein X is dynamicallyindicated or semi-statically configured, in case the first fieldindicates skipping PDCCH monitoring.

According to a fourth aspect provided in addition to any of first tothird aspects, the UE, in operation, selects the at least oneconfiguration parameter from a configuration table, optionally, whereinthe configuration table is configured by radio resource control, RRC.

According to a fifth aspect, provided in addition to any of first tofourth aspects, the PoSS received by the UE comprises behaviorindication and/or configuration indication for a group of UEs.

According to a sixth aspect, provided in addition to any of first tofifth aspects, the PoSS is received as a downlink control information,DCI, wherein the DCI comprises at least one first field for the behaviorindication, the first field containing a value that indicates the firstor second behavior, and wherein the DCI comprises at least one secondfield for the configuration indication, the second field containing avalue that, dependent on the value of the first field, is interpreted asindicating the at least one configuration parameter associated with thefirst or second behavior.

According to a seventh aspect provided in addition to the sixth aspect,the first field indicates to the UE to start PDCCH monitoring or not tostart PDCCH monitoring, the default behavior being not to start PDCCHmonitoring, or wherein the first field indicates to the UE to skip PDCCHmonitoring or not to skip PDCCH monitoring, the default behavior beingnot to skip PDCCH monitoring.

According to an eighth aspect provided in addition to the first to fifthaspect, the PoSS is received as a downlink control information, DCI, andwherein the behavior indication and the configuration indication arejointly encoded in a common field of the DCI.

According to a ninth aspect, which is provided in addition to the eighthand fourth aspect, the content of the common field comprises a bitmapthat is used by the UE to select the at least one configurationparameter, wherein the configuration table comprises the behaviorindication and the configuration indication.

According to a tenth aspect, which is provided in addition to the firstto fifth aspect, the PoSS is received as a downlink control information,DCI, and wherein the behavior indication is encoded as a first or secondradio network temporary identifier, RNTI, masking a cyclic redundancycheck, CRC, value of the DCI, wherein the RNTI identifies the UE andindicates the first or second behavior.

According to an eleventh aspect, which is provided in addition to thetenth and fourth aspect, the DCI comprises at least one bitmap which isused by the UE to select the at least one configuration parameter fromthe configuration table.

According to a twelfth aspect, a method is provided comprising thefollowing steps performed by a user equipment: receiving power savingsignals, PoSS, from a serving base station on which the UE is camping,monitoring the reception of PoSS to determine a UE behavior regardingprocessing of a physical downlink control channel, PDCCH, wherein thePoSS comprises a behavior indication indicating for the UE to follow afirst behavior or a second behavior, and wherein the PoSS furthercomprises a configuration indication indicating at least oneconfiguration parameter associated with the first or second behavior,and wherein the processing circuitry, determines to perform PDCCHmonitoring in case the first behavior is indicated and to skip PDCCHmonitoring in case the second behavior is indicated, and accordinglyapplies the at least one configuration parameter.

According to a thirteenth aspect, a base station, BS, is provided, whichcomprises a transmitter, which in operation, transmits power savingsignals, PoSS, to at least one user equipment, UE, which is camping onthe base station, processing circuitry, which, in operation, generatesthe PoSS, wherein the PoSS comprises a behavior indication indicatingfor the UE to follow a first behavior or a second behavior, and whereinthe PoSS further comprises a configuration indication indicating atleast one configuration parameter associated with the first or secondbehavior, and wherein the PoSS is generated to cause the UE to performPDCCH monitoring in case the first behavior is indicated and to skipPDCCH monitoring in case the second behavior is indicated, and toaccordingly apply the at least one configuration parameter.

According to a fourteenth aspect, provided in addition to the thirteenthaspect, in operation, the processing circuitry combines the PoSS for agroup of UE into a combined bitmap pattern.

According to a fifteenth aspect, provided in addition to the thirteenthor fourteenth aspect, the PoSS is transmitted as a downlink controlinformation, DCI, and the DCI comprises at least one first field for thebehavior indication, the first field containing a value that indicatesthe first or second behavior, and wherein the DCI comprises at least onesecond field for the configuration indication, the second fieldcontaining a value that, dependent on the value of the first field, isinterpreted as indicating the at least one configuration parameterassociated with the first or second behavior,

or the behavior indication and the configuration indication are jointlyencoded in a common field of the DCI,

or the behavior indication is encoded as a first or second radio networktemporary identifier, RNTI, masking a cyclic redundancy check, CRC,value of the DCI, wherein the RNTI identifies the UE and indicates thefirst or second behavior.

Hardware and Software Implementation of the Present Disclosure

The present disclosure can be realized by software, hardware, orsoftware in cooperation with hardware. Each functional block used in thedescription of each embodiment described above can be partly or entirelyrealized by an LSI such as an integrated circuit, and each processdescribed in the each embodiment may be controlled partly or entirely bythe same LSI or a combination of LSIs. The LSI may be individuallyformed as chips, or one chip may be formed so as to include a part orall of the functional blocks. The LSI may include a data input andoutput coupled thereto. The LSI here may be referred to as an IC(integrated circuit), a system LSI, a super LSI, or an ultra LSIdepending on a difference in the degree of integration. However, thetechnique of implementing an integrated circuit is not limited to theLSI and may be realized by using a dedicated circuit, a general-purposeprocessor, or a special-purpose processor. In addition, a FPGA (FieldProgrammable Gate Array) that can be programmed after the manufacture ofthe LSI or a reconfigurable processor in which the connections and thesettings of circuit cells disposed inside the LSI can be reconfiguredmay be used. The present disclosure can be realized as digitalprocessing or analogue processing. If future integrated circuittechnology replaces LSIs as a result of the advancement of semiconductortechnology or other derivative technology, the functional blocks couldbe integrated using the future integrated circuit technology.Biotechnology can also be applied.

The present disclosure can be realized by any kind of apparatus, device,or system having a function of communication, which is referred as acommunication apparatus.

Some non-limiting examples of such communication apparatus include aphone (e.g., cellular (cell) phone, smart phone), a tablet, a personalcomputer (PC) (e.g., laptop, desktop, netbook), a camera (e.g., digitalstill/video camera), a digital player (digital audio/video player), awearable device (e.g., wearable camera, smart watch, tracking device), agame console, a digital book reader, a telehealth/telemedicine (remotehealth and medicine) device, and a vehicle providing communicationfunctionality (e.g., automotive, airplane, ship), and variouscombinations thereof.

The communication apparatus is not limited to be portable or movable,and may also include any kind of apparatus, device or system beingnon-portable or stationary, such as a smart home device (e.g., anappliance, lighting, smart meter, control panel), a vending machine, andany other “things” in a network of an “Internet of Things (IoT).

The communication may include exchanging data through, for example, acellular system, a wireless LAN system, a satellite system, etc., andvarious combinations thereof.

The communication apparatus may comprise a device such as a controlleror a sensor, which is coupled to a communication device performing afunction of communication described in the present disclosure. Forexample, the communication apparatus may comprise a controller or asensor that generates control signals or data signals, which are used bya communication device performing a communication function of thecommunication apparatus.

The communication apparatus also may include an infrastructure facility,such as a base station, an access point, and any other apparatus,device, or system that communicates with or controls apparatuses such asthose in the above non-limiting examples.

Further, the various embodiments may also be implemented by means ofsoftware modules, which are executed by a processor or directly inhardware. Also a combination of software modules and a hardwareimplementation may be possible. The software modules may be stored onany kind of computer readable storage media, for example, RAM, EPROM,EEPROM, flash memory, registers, hard disks, CD-ROM, DVD, etc. It shouldbe further noted that the individual features of the differentembodiments may individually or in arbitrary combination be subjectmatter to another embodiment.

It would be appreciated by a person skilled in the art that numerousvariations and/or modifications may be made to the present disclosure asshown in the specific embodiments. The present embodiments are,therefore, to be considered in all respects to be illustrative and notrestrictive.

The various embodiments described above can be combined to providefurther embodiments. All of the U.S. patents, U.S. patent applicationpublications, U.S. patent applications, foreign patents, foreign patentapplications and non-patent publications referred to in thisspecification and/or listed in the Application Data Sheet areincorporated herein by reference, in their entirety. Aspects of theembodiments can be modified, if necessary to employ concepts of thevarious patents, applications and publications to provide yet furtherembodiments.

These and other changes can be made to the embodiments in light of theabove-detailed description. In general, in the following claims, theterms used should not be construed to limit the claims to the specificembodiments disclosed in the specification and the claims, but should beconstrued to include all possible embodiments along with the full scopeof equivalents to which such claims are entitled. Accordingly, theclaims are not limited by the disclosure.

1. A user equipment, UE, comprising: a receiver, which in operation,receives power saving signals, PoSS, from a serving base station onwhich the UE is camping; and processing circuitry, which, in operation,monitors the reception of PoSS to determine a UE behavior regardingprocessing of a physical downlink control channel, PDCCH, wherein thePoSS comprises a behavior indication indicating for the UE to follow afirst behavior or a second behavior, and wherein the PoSS furthercomprises a configuration indication indicating at least oneconfiguration parameter associated with the first or second behavior;and wherein the processing circuitry, in operation, determines toperform PDCCH monitoring in case the first behavior is indicated and toskip PDCCH monitoring in case the second behavior is indicated, andaccordingly applies the at least one configuration parameter.
 2. Theuser equipment according to claim 1, wherein, in case the first fieldindicates performing PDCCH monitoring, the at least one configurationparameter comprises at least one or a combination of: Channel StateInformation (CSI) reference resources, Radio resource management (RRM)reference resources, CSI reporting resources, RRM reporting resources,Sounding Reference Signal, SRS, transmission resources,quasi-co-location of CSI/RRM reference resources, quasi-co-location ofCSI report resources, RRM report resources and/or SRS transmissionresources, Control-Resource Set, CORESET information, Search spaceinformation, a set of slots for PDCCH monitoring, PoSS monitoringskipping, Hybrid Automatic Repeat Request-Acknowledgement, HARQ-ACK,resource parameter indication.
 3. The user equipment according to claim1, wherein the at least one configuration parameter comprises one ofskipping PDCCH monitoring and/or PoSS monitoring until the nextsemi-static DRX cycle, or until the next occasion of a configured powersaving signal/channel, or in the next X slots, wherein X is dynamicallyindicated or semi-statically configured, in case the first fieldindicates skipping PDCCH monitoring.
 4. The user equipment according toclaim 1, wherein the UE, in operation, selects the at least oneconfiguration parameter from a configuration table, wherein theconfiguration table is configured by radio resource control, RRC.
 5. Theuser equipment according to claim 1, wherein the PoSS received by the UEcomprises behavior indication and/or configuration indication for agroup of UEs.
 6. The user equipment according to claim 1, wherein thePoSS is received as a downlink control information, DCI, wherein the DCIcomprises at least one first field for the behavior indication, thefirst field containing a value that indicates the first or secondbehavior, and wherein the DCI comprises at least one second field forthe configuration indication, the second field containing a value that,dependent on the value of the first field, is interpreted as indicatingthe at least one configuration parameter associated with the first orsecond behavior.
 7. The user equipment according to claim 6, wherein thefirst field indicates to the UE to start PDCCH monitoring or not tostart PDCCH monitoring, the default behavior being not to start PDCCHmonitoring, or wherein the first field indicates to the UE to skip PDCCHmonitoring or not to skip PDCCH monitoring, the default behavior beingnot to skip PDCCH monitoring.
 8. The user equipment according to claim1, wherein the PoSS is received as a downlink control information, DCI,and wherein the behavior indication and the configuration indication arejointly encoded in a common field of the DCI.
 9. The user equipmentaccording to claim 8, wherein the content of the common field comprisesa bitmap that is used by the UE to select the at least one configurationparameter, wherein the configuration table comprises the behaviorindication and the configuration indication.
 10. The user equipmentaccording to one of the claim 1, wherein the PoSS is received as adownlink control information, DCI, and wherein the behavior indicationis encoded as a first or second radio network temporary identifier,RNTI, masking a cyclic redundancy check, CRC, value of the DCI, whereinthe RNTI identifies the UE and indicates the first or second behavior.11. The user equipment according to claim 10, wherein the DCI comprisesat least one bitmap which is used by the UE to select the at least oneconfiguration parameter from the configuration table.
 12. A methodcomprising the following steps performed by a user equipment, UE:receiving power saving signals, PoSS, from a serving base station onwhich the UE is camping; monitoring the reception of PoSS to determine aUE behavior regarding processing of a physical downlink control channel,PDCCH; wherein the PoSS comprises a behavior indication indicating forthe UE to follow a first behavior or a second behavior, and wherein thePoSS further comprises a configuration indication indicating at leastone configuration parameter associated with the first or secondbehavior; and wherein the processing circuitry, determines to performPDCCH monitoring in case the first behavior is indicated and to skipPDCCH monitoring in case the second behavior is indicated, andaccordingly applies the at least one configuration parameter.
 13. A basestation, BS, comprising: a transmitter, which in operation, transmitspower saving signals, PoSS, to at least one user equipment, UE, which iscamping on the base station; and processing circuitry, which, inoperation, generates the PoSS, wherein the PoSS comprises a behaviorindication indicating for the UE to follow a first behavior or a secondbehavior, and wherein the PoSS further comprises a configurationindication indicating at least one configuration parameter associatedwith the first or second behavior; and wherein the PoSS is generated tocause the UE to perform PDCCH monitoring in case the first behavior isindicated and to skip PDCCH monitoring in case the second behavior isindicated, and to accordingly apply the at least one configurationparameter.
 14. The base station according to claim 13, wherein, inoperation, the processing circuitry combines the PoSS for a group of UEinto a combined bitmap pattern.
 15. The base station according to claim13, wherein the PoSS is transmitted as a downlink control information,DCI, and wherein the DCI comprises at least one first field for thebehavior indication, the first field containing a value that indicatesthe first or second behavior, and wherein the DCI comprises at least onesecond field for the configuration indication, the second fieldcontaining a value that, dependent on the value of the first field, isinterpreted as indicating the at least one configuration parameterassociated with the first or second behavior, or wherein the behaviorindication and the configuration indication are jointly encoded in acommon field of the DCI, or wherein the behavior indication is encodedas a first or second radio network temporary identifier, RNTI, masking acyclic redundancy check, CRC, value of the DCI, wherein the RNTIidentifies the UE and indicates the first or second behavior.